public async void CanUseRateLimit()
{
Assert.True(LimitRequestZone.TryParse("zone=mylimit rate=10r/s", out var limitRequestZone));
var delay = new MockDelay();
var queue = new LeakyBucket(limitRequestZone, delay);
Assert.Equal(1, queue.RemainingSlots);
Assert.Equal(0, queue.UsedSlots);
// 1st request should be processed immediately
var wait = queue.Throttle();
var processing = queue.DrainNext();
Assert.True(wait.Wait(10));
Assert.Equal(0, queue.RemainingSlots);
Assert.Equal(1, queue.UsedSlots);
// 2nd request should be rejected
Assert.False(await queue.Throttle());
// Can't process, as we need to throttle
Assert.False(processing.Wait(10));
delay.AdvanceMilliseconds(99);
Assert.False(processing.Wait(10));
// Though after 100ms, it should works
delay.AdvanceMilliseconds(1);
Assert.True(processing.Wait(10));
Assert.Equal(1, queue.RemainingSlots);
Assert.Equal(0, queue.UsedSlots);
processing = queue.DrainNext();
await queue.Throttle();
}
public async void CanThrottle()
{
Assert.True(LimitRequestZone.TryParse("zone=mylimit rate=10r/s burst=20", out var limitRequestZone));
var delay = new MockDelay();
var service = new RateLimitService(delay);
await Assert.ThrowsAsync <KeyNotFoundException>(async() => await service.Throttle("mylimit"));
Assert.Equal(0, service.BucketsCount);
service.SetZone(limitRequestZone);
var throttling = service.Throttle("mylimit"); // Will execute immediately, slot reserved until +100
Assert.True(throttling.Wait(10));
Assert.Equal(1, service.BucketsCount);
var throttling2 = service.Throttle("mylimit"); // Will execute at +100, slot reserved until +200
Assert.False(throttling2.Wait(10));
Assert.Equal(1, service.BucketsCount);
delay.AdvanceMilliseconds(100);
Assert.True(throttling2.Wait(10));
Assert.True(throttling2.IsCompletedSuccessfully);
Assert.Equal(1, service.BucketsCount); // Still bucket 1, because the slot used by throttling2 is still here
delay.AdvanceMilliseconds(100); // The bucket should be empty, though but wait one more period before deleting the bucket
Thread.Sleep(10);
Assert.Equal(1, service.BucketsCount);
delay.AdvanceMilliseconds(100);
Thread.Sleep(100);
Assert.Equal(0, service.BucketsCount);
}
public void CanUseRateLimitWithBurstNoDelay()
{
Assert.True(LimitRequestZone.TryParse("zone=mylimit rate=10r/s burst=20 nodelay", out var limitRequestZone));
var delay = new MockDelay();
var queue = new LeakyBucket(limitRequestZone, delay);
Assert.Equal(20, queue.RemainingSlots);
Assert.Equal(0, queue.UsedSlots);
// 1st request should be processed immediately
var wait = queue.Throttle();
var processing = queue.DrainNext();
Assert.True(wait.Wait(10));
Assert.Equal(19, queue.RemainingSlots);
Assert.Equal(1, queue.UsedSlots);
Assert.True(processing.Wait(10)); // Thanks to nodelay processing do not have to wait
// 2nd request should be processed immediately, but the slot kept
wait = queue.Throttle();
processing = queue.DrainNext();
Assert.True(wait.Wait(10));
Assert.True(processing.Wait(10)); // Thanks to nodelay processing do not have to wait
Assert.Equal(18, queue.RemainingSlots); // But the slots should not be free
Assert.Equal(2, queue.UsedSlots);
// Can process, thanks to nodelay
delay.AdvanceMilliseconds(99);
Assert.Equal(18, queue.RemainingSlots);
Assert.Equal(2, queue.UsedSlots);
// Though after 100ms, one slot should be freed, and the queued task executed
delay.AdvanceMilliseconds(1);
Thread.Sleep(1); // Sleep necessary as the WaitAfter is running concurrently
Assert.Equal(19, queue.RemainingSlots);
Assert.Equal(1, queue.UsedSlots);
Thread.Sleep(1); // Sleep necessary as the WaitAfter is running concurrently
// +100 ms passed, second slot if released
delay.AdvanceMilliseconds(99);
Assert.Equal(19, queue.RemainingSlots);
delay.AdvanceMilliseconds(1);
Thread.Sleep(1); // Sleep necessary as the WaitAfter is running concurrently
Assert.Equal(20, queue.RemainingSlots);
}
public void CanUseRateLimitWithBurst()
{
Assert.True(LimitRequestZone.TryParse("zone=mylimit rate=10r/s burst=20", out var limitRequestZone));
var delay = new MockDelay();
var queue = new LeakyBucket(limitRequestZone, delay);
Assert.Equal(20, queue.RemainingSlots);
Assert.Equal(0, queue.UsedSlots);
// 1st request should be processed immediately
var wait = queue.Throttle();
var processing = queue.DrainNext();
Assert.True(wait.Wait(10));
Assert.Equal(19, queue.RemainingSlots);
Assert.Equal(1, queue.UsedSlots);
// 2nd request should be queued
wait = queue.Throttle();
Assert.False(wait.Wait(10));
Assert.Equal(18, queue.RemainingSlots);
Assert.Equal(2, queue.UsedSlots);
// Can't process, as we need to throttle
Assert.False(processing.Wait(10));
delay.AdvanceMilliseconds(99);
Assert.False(processing.Wait(10));
Assert.False(wait.Wait(10));
// Though after 100ms, one slot should be freed, and the queued task executed
delay.AdvanceMilliseconds(1);
Assert.True(processing.Wait(10));
processing = queue.DrainNext();
Assert.True(wait.Wait(10));
Assert.Equal(19, queue.RemainingSlots);
Assert.Equal(1, queue.UsedSlots);
// But still processing blocked...
Assert.False(processing.Wait(10));
// Until 100 ms passed
delay.AdvanceMilliseconds(100);
Assert.True(processing.Wait(10));
Assert.Equal(20, queue.RemainingSlots);
}
public async void CanUseRateLimitWithBurstNoDelay2()
{
Assert.True(LimitRequestZone.TryParse("zone=mylimit rate=10r/s burst=20 nodelay", out var limitRequestZone));
var delay = new MockDelay();
var queue = new LeakyBucket(limitRequestZone, delay);
List <Task> waits = new List <Task>();
for (int i = 0; i < 20; i++)
{
waits.Add(queue.Throttle());
}
Assert.False(await queue.Throttle());
for (int i = 0; i < 20; i++)
{
delay.AdvanceMilliseconds(100);
var processing = queue.DrainNext();
Task.WaitAny(waits.ToArray());
waits.RemoveAll(t => t.IsCompletedSuccessfully);
Assert.Equal(20 - i - 1, waits.Count);
Assert.True(processing.IsCompletedSuccessfully);
}
}